code: def testLineBreakBounded(self):
      barFeed = self.__getFeed()
      bars = barFeed[LineBreakTestCase.Instrument]
  
      # Invalid maxLen, smaller than reversalLines.
      with self.assertRaises(Exception):
          lineBreak = linebreak.LineBreak(bars, 3, maxLen=2)
  
      lineBreak = linebreak.LineBreak(bars, 3, maxLen=4)
      # Invalid maxLen, smaller than reversalLines.
      with self.assertRaises(Exception):
          lineBreak.setMaxLen(2)
      barFeed.loadAll()
  
      self.assertEqual(len(lineBreak), 4)
      self.assertEqual(len(lineBreak[:]), 4)
      self.assertEqual(len(lineBreak.getDateTimes()), 4)
      self.assertEqual(lineBreak[-1].getLow(), 10.76)
      self.assertEqual(lineBreak[-1].getHigh(), 10.92)
      self.assertEqual(lineBreak[-1].isWhite(), False)
      self.assertEqual(lineBreak[-1].isBlack(), True)
  
file_path: pyalgotrade/testcases/technical_linebreak_test.py
imports: import datetime
  from .None import common
  from pyalgotrade.technical import linebreak
  from pyalgotrade.barfeed import yahoofeed
  from pyalgotrade import dataseries
  from pyalgotrade import bar
  from pyalgotrade.dataseries import bards
label_desc: Use image node_id 4 for calling the LineBreakTestCase obj's underlying member method code with example usage: obj.testLineBreakBounded() without return types